Out of nowhere comes a young black man of princely bearing and poetic mien, with the promise to transcend race and the rancor of our politics. The nation is beguiled.

But before he can become the Democratic nominee for president, Obama must complete three labors.

First, he must attract white votes in the heartland. That he does, in Iowa, and again in New Hampshire. Then he must demonstrate that he can win black votes without losing all his white support in the racially polarized South. That he does in South Carolina.

Now, on Super Tuesday, he must prove his appeal beyond black and white by winning the support of Latinos and Asian-Americans in states _ beginning with California _ where so many of them live.

It would seem the simplest labor of the three. “He would be a president who would reflect the diversity of America in his very being, in his very biography,” said Angelica Jongco, a 29-year-old Filipino-American attorney from San Francisco. White mother, African father. A childhood in Indonesia and Hawaii. Kin of every color.

But it appears Tuesday will test the scope of Obama’s transcendence, the fate of this most multicultural presidential candidate hinging on the very communities that have made America so diverse.

The irony is not lost on the Obama campaign.

U.S. Rep. Luis Gutierrez, the Chicago Democrat who is Obama’s top Hispanic advocate and adviser, describes their Super Tuesday paradox: “It’s so astonishing to have young whites in the Dixieland South voting overwhelmingly for Obama and yet (not knowing), will Latinos do it?”

In the way Gutierrez frames the question may be the kernel of an answer _ and the challenge.

Obama’s moving victory speeches in Iowa and South Carolina were met with chills and tears. At his South Carolina celebration, supporters chanted, “Race doesn’t matter.” His candidacy at times seems less a campaign than a crusade to transform the political culture and, implicitly, to bind the nation’s racial wounds.

But that powerful symbolism doesn’t resonate as powerfully with everyone.

“It’s less symbolic for Latinos than it is for whites,” said Rodolfo de la Garza, a political scientist at ColumbiaUniversity in New York and vice president for research of the Tomas Rivera Policy Institute.

If some whites find absolution in Obama’s candidacy, Latinos don’t need it. “Whites have been the ones persecuting blacks,” de la Garza said.

S.B. Woo, a former Democratic lieutenant governor of Delaware and founder of the 80-20 Initiative, an Asian-American political action committee, said the same holds true for his ethnic group. “We don’t have the guilt I’ve seen many of my white friends have, because Asian-Americans were not present, so to speak, when blacks were being discriminated against,” Woo said.

This doesn’t mean Latinos or Asians won’t vote for black candidates, as Sergio Bendixen, Hillary Clinton’s Hispanic pollster, suggested with regard to Hispanics. “The Hispanic voter _ and I want to say this very carefully _ has not shown a lot of willingness or affinity to support black candidates,” he told The New Yorker magazine.

There is plenty of contrary evidence _ from the Rev. Jesse Jackson’s presidential campaigns to numerous congressional and mayoral campaigns, including David Dinkins in New York and Harold Washington in Chicago. And a recent national survey of Latino opinion leaders, conducted by Angelo Falcon of the National Institute for Latino Policy in New York, found little support for Bendixen’s assertion. Still, nearly 80 percent of the respondents thought Latino voters would rally behind Clinton.

Among Latinos, the former first lady is better known than Obama. She has worked longer and harder for their support.

“Hillary has earned her strong position with the Latino community,” said Simon Rosenberg, head of the New Democrat Network, a Washington, D.C., advocacy group that is not taking sides. “Obama’s been a little late to the Hispanic party.”

Nicholas Vaca, a lawyer in San Jose, Calif., is author of “The Presumed Alliance: the Unspoken Conflict Between Latinos and Blacks and What it Means for America.”

“They were so giddy over having an African-American who was going to transcend racial politics that they neglected to consider the Latino vote,” Vaca said of the Obama campaign. “If he cannot carry the Latino vote, he is not going to be the candidate.”

Twenty-two states will hold Democratic primaries and caucuses Tuesday. They include seven of the 10 with the largest percentage of eligible Hispanic voters _ New Mexico, California, New York, Arizona, New Jersey, Illinois and Connecticut. They include three of the five states with the largest percentage of Asian eligible voters _ California, New Jersey and New York.

California is the biggest prize and far from the home turf of either candidate.

In mid-January, the Field Poll found Clinton leading Obama there by 12 percentage points, with 20 percent undecided. Obama was well ahead among California‘s black voters, and neck-and-neck with Clinton among whites. But he trailed far behind Clinton among Latino and Asian voters who together could represent as much as a quarter of the Democratic vote.

Clinton swamped Obama with Latino voters in the Jan. 19 Nevada caucuses and in the unsanctioned Jan. 29 primary in Florida.

But Obama approaches Super Tuesday on a roll, coming off his victory in South Carolina and his endorsement by Caroline Kennedy and her uncle, Massachusetts Sen. Edward M. Kennedy, who has strong ties with the Latino community.

Obama brings “an aspirational message that immigrants can tap into,” said Gregory Rodriguez, a Southern California columnist with both Time magazine and the Los Angeles Times. And Rodriguez believes the symbolism of Obama’s campaign is not lost on the 75 percent of Latino voters who are native-born.

To close the gap, said political scientist Bruce Cain, director of the University of California Washington Center, Obama must move beyond his base of blacks and “white wine” whites by reclaiming the fullness of his identity.

It’s the complexity of Obama’s identity that appeals to Angelica Jongco.

“What I really like about him is he is somebody who is very comfortable in his own skin,” said Jongco, the daughter of Filipino immigrants who live in South Orange, N.J., where she grew up. “He’s thought a lot about what each aspect of his identity means.”

And she connects with it: “He lived in Indonesia. He is able to relate to a grandmother in Kenya who doesn’t have running water. That is something many Filipinos can relate to.”

But to S.B. Woo this is no substitute for substance: “He thinks he’s doing us such a great big favor. We are looking for concrete commitments showing that he understands the plight that new immigrants face.”

Woo’s PAC is actively supporting Clinton in California, where it can have the most impact, because her campaign agreed in mid-December to 80-20’s call for measures to root out employment discrimination against Asian-Americans and increase their numbers in the federal judiciary. Obama’s didn’t until Thursday.

Early negotiations with young Obama staffers did not go so well.

“They told me he has a brother-in-law who’s an Asian-American and I should feel very happy about that,” Woo recalled. “What is this? This is not feudal China. Such farcical statements, I can’t believe people say such things in America.”

“Younger Asian-Americans are much more cognizant of the significance of the Obama campaign, both in terms of racial history but also in terms of the other transformative language he uses,” Ko said.

And while Ko said his parents, staunch Republicans, don’t believe a black candidate can be elected president, “I do think they kind of want their pessimism to be disproved so that people who are a minority have a real shot in this country.”